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Solve a whole problem, not just one number.Curated calculator paths for real-world scenarios.
Make sense of your paycheck
Convert salary to hourly, check overtime pay, and see your real annual income before taxes.
Lose weight the right way
Find your maintenance calories, set a safe deficit, and track body fat — no fad diet.
Renovate a room
Measure the space, then get exact paint, flooring and material quantities before you buy.
Plan a road trip
Convert distances, project fuel cost, and pin down the dates before you leave.
Keep track of dates
Age in any unit, days between two dates, and the next expiration on a label.
Shrink your carbon footprint
Measure the big three — diet, flights and plastic — then find where to cut.
Top calculators
Days Between Dates Calculator
Count the days, weeks, months, and business days between any two dates. Handles leap years, the inclusive-vs-exclusive q…
Open #2 HomeRoof Pitch Calculator
Convert between roof pitch ratio (x:12), angle in degrees, and percent slope. Includes rafter length from horizontal run…
Open #3 ConvertUniversal Unit Conversion Calculator
One conversion calculator for length, weight, volume, temperature, area, speed, and time. Built-in support for metric, i…
Open #4 ConvertOunces to Cups Converter
Convert fluid ounces to cups. Default is the US customary cup at exactly 8 fl oz, but recipes from Europe, the UK, and J…
Open #5 ConvertKilometers to Miles Converter
Convert between kilometers and miles using the exact international factor (1 mile = 1.609344 km). Includes common race d…
Open #6 HealthRunning Pace Calculator
Running pace calculator. Enter distance and elapsed time; get pace per kilometre, pace per mile, speed in km/h and mph, …
Open #7 MoneyMarkup Calculator
Calculate markup, selling price, profit, and margin from any two of cost, markup percent, or selling price. The retailer…
Open #8 HomeAir Changes Per Hour Calculator
Compute ACH (air changes per hour) for any room. Enter dimensions or volume and airflow in CFM or m³/h. Compare aga…
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